[linux.git] / net / ipv4 / metrics.c

// SPDX-License-Identifier: GPL-2.0-only
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/types.h>
#include <net/ip.h>
#include <net/net_namespace.h>
#include <net/tcp.h>

static int ip_metrics_convert(struct net *net, struct nlattr *fc_mx,
			      int fc_mx_len, u32 *metrics,
			      struct netlink_ext_ack *extack)
{
	bool ecn_ca = false;
	struct nlattr *nla;
	int remaining;

	if (!fc_mx)
		return 0;

	nla_for_each_attr(nla, fc_mx, fc_mx_len, remaining) {
		int type = nla_type(nla);
		u32 val;

		if (!type)
			continue;
		if (type > RTAX_MAX) {
			NL_SET_ERR_MSG(extack, "Invalid metric type");
			return -EINVAL;
		}

		if (type == RTAX_CC_ALGO) {
			char tmp[TCP_CA_NAME_MAX];

			nla_strlcpy(tmp, nla, sizeof(tmp));
			val = tcp_ca_get_key_by_name(net, tmp, &ecn_ca);
			if (val == TCP_CA_UNSPEC) {
				NL_SET_ERR_MSG(extack, "Unknown tcp congestion algorithm");
				return -EINVAL;
			}
		} else {
			if (nla_len(nla) != sizeof(u32)) {
				NL_SET_ERR_MSG_ATTR(extack, nla,
						    "Invalid attribute in metrics");
				return -EINVAL;
			}
			val = nla_get_u32(nla);
		}
		if (type == RTAX_ADVMSS && val > 65535 - 40)
			val = 65535 - 40;
		if (type == RTAX_MTU && val > 65535 - 15)
			val = 65535 - 15;
		if (type == RTAX_HOPLIMIT && val > 255)
			val = 255;
		if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK)) {
			NL_SET_ERR_MSG(extack, "Unknown flag set in feature mask in metrics attribute");
			return -EINVAL;
		}
		metrics[type - 1] = val;
	}

	if (ecn_ca)
		metrics[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;

	return 0;
}

struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx,
					int fc_mx_len,
					struct netlink_ext_ack *extack)
{
	struct dst_metrics *fib_metrics;
	int err;

	if (!fc_mx)
		return (struct dst_metrics *)&dst_default_metrics;

	fib_metrics = kzalloc(sizeof(*fib_metrics), GFP_KERNEL);
	if (unlikely(!fib_metrics))
		return ERR_PTR(-ENOMEM);

	err = ip_metrics_convert(net, fc_mx, fc_mx_len, fib_metrics->metrics,
				 extack);
	if (!err) {
		refcount_set(&fib_metrics->refcnt, 1);
	} else {
		kfree(fib_metrics);
		fib_metrics = ERR_PTR(err);
	}

	return fib_metrics;
}
EXPORT_SYMBOL_GPL(ip_fib_metrics_init);
Commit	Line	Data
457c8996	1	// SPDX-License-Identifier: GPL-2.0-only
a919525a DA	2	#include <linux/netlink.h>
	3	#include <linux/rtnetlink.h>
	4	#include <linux/types.h>
	5	#include <net/ip.h>
	6	#include <net/net_namespace.h>
	7	#include <net/tcp.h>
	8
767a2217	9	static int ip_metrics_convert(struct net net, struct nlattr fc_mx,
d7e774f3 DA	10	int fc_mx_len, u32 *metrics,
d7e774f3 DA	11	struct netlink_ext_ack *extack)
a919525a DA	12	{
	13	bool ecn_ca = false;
	14	struct nlattr *nla;
	15	int remaining;
	16
	17	if (!fc_mx)
	18	return 0;
	19
	20	nla_for_each_attr(nla, fc_mx, fc_mx_len, remaining) {
	21	int type = nla_type(nla);
	22	u32 val;
	23
	24	if (!type)
	25	continue;
d7e774f3 DA	26	if (type > RTAX_MAX) {
d7e774f3 DA	27	NL_SET_ERR_MSG(extack, "Invalid metric type");
a919525a	28	return -EINVAL;
d7e774f3	29	}
a919525a DA	30
	31	if (type == RTAX_CC_ALGO) {
	32	char tmp[TCP_CA_NAME_MAX];
	33
	34	nla_strlcpy(tmp, nla, sizeof(tmp));
	35	val = tcp_ca_get_key_by_name(net, tmp, &ecn_ca);
d7e774f3 DA	36	if (val == TCP_CA_UNSPEC) {
d7e774f3 DA	37	NL_SET_ERR_MSG(extack, "Unknown tcp congestion algorithm");
a919525a	38	return -EINVAL;
d7e774f3	39	}
a919525a	40	} else {
d7e774f3 DA	41	if (nla_len(nla) != sizeof(u32)) {
	42	NL_SET_ERR_MSG_ATTR(extack, nla,
	43	"Invalid attribute in metrics");
5b5e7a0d	44	return -EINVAL;
d7e774f3	45	}
a919525a DA	46	val = nla_get_u32(nla);
	47	}
	48	if (type == RTAX_ADVMSS && val > 65535 - 40)
	49	val = 65535 - 40;
	50	if (type == RTAX_MTU && val > 65535 - 15)
	51	val = 65535 - 15;
	52	if (type == RTAX_HOPLIMIT && val > 255)
	53	val = 255;
d7e774f3 DA	54	if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK)) {
d7e774f3 DA	55	NL_SET_ERR_MSG(extack, "Unknown flag set in feature mask in metrics attribute");
a919525a	56	return -EINVAL;
d7e774f3	57	}
a919525a DA	58	metrics[type - 1] = val;
	59	}
	60
	61	if (ecn_ca)
	62	metrics[RTAX_FEATURES - 1] \|= DST_FEATURE_ECN_CA;
	63
	64	return 0;
	65	}
767a2217 DA	66
767a2217 DA	67	struct dst_metrics ip_fib_metrics_init(struct net net, struct nlattr *fc_mx,
d7e774f3 DA	68	int fc_mx_len,
d7e774f3 DA	69	struct netlink_ext_ack *extack)
767a2217 DA	70	{
	71	struct dst_metrics *fib_metrics;
	72	int err;
	73
	74	if (!fc_mx)
	75	return (struct dst_metrics *)&dst_default_metrics;
	76
	77	fib_metrics = kzalloc(sizeof(*fib_metrics), GFP_KERNEL);
	78	if (unlikely(!fib_metrics))
	79	return ERR_PTR(-ENOMEM);
	80
d7e774f3 DA	81	err = ip_metrics_convert(net, fc_mx, fc_mx_len, fib_metrics->metrics,
d7e774f3 DA	82	extack);
767a2217 DA	83	if (!err) {
	84	refcount_set(&fib_metrics->refcnt, 1);
	85	} else {
	86	kfree(fib_metrics);
	87	fib_metrics = ERR_PTR(err);
	88	}
	89
	90	return fib_metrics;
	91	}
	92	EXPORT_SYMBOL_GPL(ip_fib_metrics_init);